THREE AND EASY: Rookie Redskins quarterback Robert Griffin III celebrates a touchdown throw — one of two on the day — during yesterday’s shock upset of the Saints in New Orleans. Photo: Getty Images

NEW ORLEANS — Robert Griffin III brought his Heisman Trophy swagger to New Orleans and made his NFL debut look like a Big Easy.

Showing a veteran’s composure by scrambling only when necessary, the dynamic Redskins rookie quarterback tormented New Orleans’ defense with 320 yards passing and two touchdowns, and Washington held on for 40-32 victory over the Saints yesterday.

“I’ve won a high school state championship and a bowl game in college, but to play in the NFL, the pinnacle of it all, and win your first game against a Hall of Famer in Drew Brees, it’s at the top,” Griffin said while cradling the game ball he had just been given. “After the game, [Brees] told me he was proud of me. That’s big for him to say after he just lost the game.”

New Orleans hoped to open the season with a defiant show of force in the wake of the bounty scandal that overshadowed its offseason. The Saints also got a boost Friday when a three-member appeals panel reinstated defensive end Will Smith and linebacker Jon Vilma, who had been suspended for their roles in the Saints’ alleged pay-for-pain bounty program.

Smith started, while Vilma, deemed unfit to play after offseason knee surgery, received a rousing ovation when he walked onto the field to lead the Saints’ traditional pregame “Who-dat” chant.

But the Saints spent much of the game trying to keep up with a Redskins offense powered by youth. Opening with several short, quick throws, Griffin completed his first eight passes. His seventh pass, released just before he was leveled by blitzing safety Malcolm Jenkins, hit Pierre Garcon in stride over the middle for an 88-yard touchdown, tying the second-longest scoring pass by a quarterback making his NFL debut.

“It’s great for any quarterback to get a couple of easy passes at the beginning of a game so you can get into a rhythm,” Griffin said.

Griffin finished 19 of 26 with no interceptions and a passer rating of 139.9. He also scrambled for 42 yards.

“Robert did an unbelievable job to play the way that he did in his first game in the National Football League,” said Redskins coach Mike Shanahan, marveling at “the poise that he played with and some of the throws that he made.”

Rookie Alfred Morris rushed for 96 yards and two touchdowns.

Brees quickly dismissed the idea that disruptions from the bounty probe, which resulted in a season-long suspension for coach Sean Payton, were to blame.

“Not at all. It’s the NFL. You better bring it every week,” said Brees, who completed 24 of 52 passes for 339 yards and three touchdowns.

The Saints pulled to 40-32 on Darren Sproles’ 2-yard reception. But when Washington required a first down to all but put the game away, Griffin delivered a 22-yard strike to tight end Logan Paulsen.